/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.apis.graphics;

import android.content.Context;
import android.graphics.*;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.Window;

public class UnicodeChart extends GraphicsActivity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		requestWindowFeature(Window.FEATURE_NO_TITLE);

		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {
		private Paint mBigCharPaint;
		private Paint mLabelPaint;
		private final char[] mChars = new char[256];
		private final float[] mPos = new float[512];

		private int mBase;

		private static final int XMUL = 20;
		private static final int YMUL = 28;
		private static final int YBASE = 18;

		public SampleView(Context context) {
			super(context);
			setFocusable(true);
			setFocusableInTouchMode(true);

			mBigCharPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
			mBigCharPaint.setTextSize(15);
			mBigCharPaint.setTextAlign(Paint.Align.CENTER);

			mLabelPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
			mLabelPaint.setTextSize(8);
			mLabelPaint.setTextAlign(Paint.Align.CENTER);

			// the position array is the same for all charts
			float[] pos = mPos;
			int index = 0;
			for (int col = 0; col < 16; col++) {
				final float x = col * XMUL + 10;
				for (int row = 0; row < 16; row++) {
					pos[index++] = x;
					pos[index++] = row * YMUL + YBASE;
				}
			}
		}

		private float computeX(int index) {
			return (index >> 4) * XMUL + 10;
		}

		private float computeY(int index) {
			return (index & 0xF) * YMUL + YMUL;
		}

		private void drawChart(Canvas canvas, int base) {
			char[] chars = mChars;
			for (int i = 0; i < 256; i++) {
				int unichar = base + i;
				chars[i] = (char) unichar;

				canvas.drawText(Integer.toHexString(unichar), computeX(i),
						computeY(i), mLabelPaint);
			}
			canvas.drawPosText(chars, 0, 256, mPos, mBigCharPaint);
		}

		@Override
		protected void onDraw(Canvas canvas) {
			canvas.drawColor(Color.WHITE);

			canvas.translate(0, 1);
			drawChart(canvas, mBase * 256);
		}

		@Override
		public boolean onKeyDown(int keyCode, KeyEvent event) {
			switch (keyCode) {
			case KeyEvent.KEYCODE_DPAD_LEFT:
				if (mBase > 0) {
					mBase -= 1;
					invalidate();
				}
				return true;
			case KeyEvent.KEYCODE_DPAD_RIGHT:
				mBase += 1;
				invalidate();
				return true;
			default:
				break;
			}
			return super.onKeyDown(keyCode, event);
		}
	}
}
